Active and intelligent additive, polymer and article

ABSTRACT

The present invention relates to active and intelligent additives having hybrid characteristics, that are compatible with polymers, are thermally and mechanically stable, are capable of releasing electrons and/or photons in the presence of chemical compounds, specifically amino compounds, amide compounds, oxygen reducing compounds, water or vapors thereof. The active and intelligent additives incorporate themselves into polymer matrices allowing the obtainment of active and intelligent polymeric articles. These active and intelligent polymeric articles may act as inhibitors of growth of microorganisms and fungi, as well as indicators of the presence of gasses, either in the atmosphere or caused by the decomposition of foodstuffs, for example.

TECHNICAL FIELD

The present invention relates to active and intelligent additives havinghybrid characteristics, that are compatible with polymers, are thermallyand mechanically stable, are capable of releasing electrons and/orphotons in the presence of chemical compounds, specifically aminocompounds, amide compounds, oxygen reducing compounds, water or vaporsthereof. The active and intelligent additives incorporate themselvesinto polymer matrices allowing the obtainment of active and intelligentpolymeric articles. These active and intelligent polymeric articles mayact as inhibitors of growth of microorganisms and fungi, as well asindicators of the presence of gasses, either in the atmosphere or causedby the decomposition of foodstuffs, for example.

PRIOR ART

The constant and increasing concern with the safety of the populationtowards attempting to warrant healthy work environments, foodstuffsevidencing good physical, chemical and nutritional characteristics, theavoidance of pro-positive contamination (bio-terrorism), among others,has been producing innumerous researches for the obtainment of specificsensors that might allow the identification and/or the control of someof such scenarios. It is therefore most important to monitor workingenvironments, for example, in some mining companies, chemical andpharmaceutical companies, viral research laboratories, foodstuffsproduction and consumption environments, among others, to warrant betterlife conditions for the workers in addition to warranting high qualityproducts for the consumers and for the public in general. Problems suchas pro-positive contamination of foodstuffs by dangerous substances(ANTHRAX, viruses, toxic metals, among others) may be identified bymeans of the use of sensors that allow, in some cases, to attack(viruses), or in other cases to detect and communicate (Anthrax andmetals), providing totally secure conditions and a better life qualityto the population.

Thus, also active and intelligent compounds, in addition to having thenecessary characteristics to monitor the previously mentionedconditions, may be used to extend the useful live of perishablefoodstuffs (acting against microorganisms) and/or to communicate thequality state of the foodstuff, whereby such compounds would allow thesupply of totally healthy foodstuffs and confirm the qualitycharacteristics thereof. In the foods packing industry there have beenused some additives that are incorporated into the packaging materials(paper, plastic, etc.) that evidence some of the characteristicspreviously mentioned herein or that might potentially act as cited aboveupon being dispersed within packaging materials.

In patent application No. US 2009/0011160 A1 there are disclosedpolymeric films on which chitosan has been immobilized on at least oneof their surfaces. Such layer of chitosan is said to be substantiallyresistant to leaching and to have a strong antimicrobial activity. Theapplication of the chitosan is made on a biaxially orientatedpolypropylene film by plasma activation of the surface at atmosphericpressure. Those films are then used in antimicrobial active foodpackaging systems. Chitosan is a compound that is sensitive both totemperature and to mechanical processing, whereby the applicationthereof onto the polymeric film is required to be performed only afterthe fabrication of the film, and further to be combined with theincidence of plasma, which implies more than one step, a higher cost andgreater complexity in processing.

In turn, patent application No. US 2006/0083710 A1 also discloses theuse of a chitosan coating for polymeric articles, however there aregrafted amino-reactive functional groups on the surface of the polymerprior to deposition of the chitosan layer. For such final coating, thereoccurs a reaction of the amino groups of the chitosan with theamino-reactive groups grafted on the surface of the polymer, stabilizingthe chitosan layer and causing the same to be at a necessaryconcentration to reduce microbial growth. In the same manner as in thepreviously cited patent application, there is a need of more than onestep in the process (grafting and application of chitosan onto thefilm), which entails implications in terms of cost and complexity of theprocess.

In patent application No. US 2007/0166399 A1 there are also claimedpolymeric articles having antimicrobial activity, particularly packages,however using as active ingredient silver compounds containing silversulfate, as well as the methods of manufacture thereof, includingmethods to whiten the articles and packages obtained by means ofstabilization of the silver sulfate. There is further described that thesilver compound layer, including silver sulfate, is sealed within thearticle or package having antimicrobial properties. It is known thatsilver is under study regarding its toxicity, which fact impacts the usethereof on packages intended for foodstuffs.

In international publication No. WO 96/23022 A1 there is disclosed theuse of a combination of terpenes or terpene derivatives with vitaminsthat are different from those terpenes as coatings having an antioxidantfunction. Such action occurs by means of electron transfer reactionsbetween the cited compounds and the oxidizer that is present. Among thevitamins that are used there are included Vitamin A and carotenes, andthe substrates that are possible to use for such coating are inorganicmaterials, natural materials, thermoplastic materials and thermosettingmaterials. Once again, these compounds are applied to the articles uponthe same being ready, which fact implies further steps and complexity ofthe process.

In patent application No. US 2005/0164169 A1 there is described the useof surface plasmon resonance for generating antibacterial,antimicrobial, hydrophilic, hydrophobic, anti-adhesive, adhesive,biological and catalytic properties, among others. There is claimed amethod of nonlinear generation using light with wavelengths ranging fromX-ray to infrared, in order to enhance the plasma (surface electrons)generation by nanometer-sized particles of noble metals orsemiconductors such as silver, copper, platinum, etc. Among the possibleapplications there may be pointed out the use as a bactericide, incorrosive preventing paints, in medical applications and buildingmaterials. Although the treatment applied on the surface of the filmconsists in only one step, it still represents an extra step after thepreparation of the said film.

Thus, the present invention introduces a novel active and intelligentadditive, which in addition to exhibiting the desired characteristics ofactivity on the final product, such as the inhibition of growth ofmicroorganisms and fungi, and the indication of the presence of analytes(gasses) and absence of toxicity, further adds the advantage of beingeasily incorporated to the polymeric matrix due to its hybrid propertywhich provides compatibility with the polymer. Such fact renderspossible the obtainment of articles, such as films, from the additizedpolymer.

Therefore, the present invention is related to an active and intelligentadditive that is compatible with polymers and which has a mode (ormechanism) of antimicrobial and indicative action that is different fromthe mechanisms found in the prior art.

Grounds of the Invention

The present invention refers to active and intelligent additives, formedby a sensitive compound encapsulated in an inorganic matrix with hybridcharacteristics, that are thermally and mechanically stable, and arecapable of releasing electrons and/or photons in the presence ofchemical compounds. The present invention also consists in theapplication of these additives to polymeric matrices whereby theresulting material may be useful in situations in which it is necessaryto know the conditions of the environment and prevent the proliferationof bacteria. Moreover, the additives according to the present inventionmay be applied to non-polar polymers used in the field of communicationsby way of electronic means and in the generation of energy and change ofthe electrical properties of the material by means of the release ofelectrons. Those characteristics can find applicability in industriessuch as in pharmaceuticals, communications, power generation,electronics, and petrochemicals, medical and environmental industries,among others.

In the present invention the active and intelligent additives may bedefined as constituting devices that are capable of releasing electronsand/or photons when they interact with certain chemical compounds. Theelectrons and/or photons release process occurs by way of a chemicalreaction of corrosion of the encapsulated sensitive chemical compound(active and intelligent additive) in contact with a reactive chemicalcompound. As a result of the corrosion there are released electronsand/or photons to the surface of the active and intelligent additive.When the active and intelligent additive is dispersed in a polymericmedium, these electrons released in the corrosion reaction will freelymigrate to the polymer surface, providing both antimicrobialcharacteristics and analyte-identifying characteristics.

Thus, when the additive according to the present invention isdispersed/incorporated in a polymeric matrix, the polymer may be used,among other applications, for the manufacture of packages that are bothactive (antimicrobial action) and intelligent (identification andcommunication of the presence of analytes by way of color change and/orquantification of the electrons having been generated and/orquantification of the protons having been generated). There may beviewed below a scheme of this corrosion reaction and the products thatare generated thereby:A+B→C+e ⁻ +hυ

Wherein:

A=Active and intelligent additive (comprising a sensitive chemicalcompound+capsule);

B=Reactive chemical compound;

C=Active and intelligent additive that does or does not change color;

e⁻=Electrons released in the reaction;

hυ=Photons released in the reaction.

SUMMARY OF THE INVENTION

The present invention relates to active and intelligent additives,formed by a sensitive compound encapsulated in an inorganic matrix withhybrid characteristics, that are thermally and mechanically stable andare capable of releasing electrons and/or photons in the presence ofchemical compounds.

For a better understanding of the invention, in the presentspecification the following terms and/or expressions should beunderstood as described below herein:

-   -   Corrosion: a chemical reaction whereby are released electrons        and/or photons that become available for migration;    -   Sensitive chemical compound: any compound capable of releasing        electrons and/or photons in the presence of a reactive chemical        compound, the said sensitive chemical compound being preferably        selected from among copper (I), sulfur, ascorbic acid and citric        acid;    -   Reactive chemical compound: any compound present in the medium        that activates the sensitive compound, wherein the said reactive        chemical compound is preferably selected from among amino        compounds, amide compounds, water, oxygen reducing agents,        and/or vapors thereof;    -   Hybrid capsule: a capsule formed by titanium or silicon        alkoxides obtained by means of a sol-gel reaction;    -   Sol-gel reaction: a hydrolytic reaction via basic or acidic        catalysis or a non-hydrolytic reaction catalyzed by a Lewis acid        (FeCl₃, AlCl₃, etc);    -   Hydrolytic reaction: a reaction employing titanium or silicon        alkoxides, water, an acid or a base, conducted at controlled        temperature, time and stirring rates;    -   Non-hydrolytic reaction: a reaction employing titanium or        silicon alkoxides, silicon tetrachloride (SiCl₄), Lewis acid,        conducted at controlled temperature, time and stirring rates;    -   Hybrid: a compound having both polar and non-polar        characteristics (organic-inorganic), since the alkoxide used for        encapsulation has a polar inorganic end (silicon or titanium)        that interacts with the sensitive compound, and a non-polar        organic chain that interacts with the matrix (polymer);    -   Mechanical stability: A characteristic of the active and        intelligent additive that protects the sensitive chemical        compound from the polymer processing conditions (shearing forces        produced by the processing machinery);    -   Thermal stability: A characteristic of the active and        intelligent additive that protects the sensitive chemical        compound against degradation or decomposition arising from the        high temperature at processing conditions.

Thus, the active and intelligent additives according to the presentinvention comprise, particularly, a sensitive compound contained withina hybrid capsule, wherein the capsule, in addition to providingmechanical and thermal stability to the sensitive compound, allows thetransfer of the generated electrons and/or photons to the surface, andalso improves the compatibility with the non-polar polymers, preferablypolyolefinic polymers, more preferably polyethylenes and polypropylenes.

The silicon alkoxides used in the present invention are preferably thetetraethyl orthosilicate, ethyl triethoxysilane, methyl triethoxysilane,phenyl triethoxysilane, methyl trimethoxysilane, n-octyl ethoxysilane,n-butyl ethoxysilane and vinyl trimethoxysilane. The titanium alkoxidesused in the present invention are preferably tetraethoxy titanium,ethyltriethoxy titanium, methyltriethoxy titanium, phenyltriethoxytitanium, n-octylethoxy titanium, n-butylethoxy titanium.

The hybridism is warranted according to the type and number ofsubstitutions in the structure of the alkoxide used. It is important topoint out that the alkoxides used are substituted with alkyl groups. Thealkyl groups are accountable for a better compatibility of the additivewith the polymeric matrix and in aiding to carry and expel the electronsto the surface of the matrix, preferably when comprising groups havingat least one double bond in their structure.

The sensitive compounds set forth in Table 1 constitute preferredexamples of compounds that may be used in the preparation of the activeand intelligent additive according to the present invention. Thesensitive compounds release a certain amount of electrons according tothe characteristic reaction for each compound.

TABLE 1 Characteristics of the sensitive compounds used in thepreparation of the additive. Decomposition Decomposition Temperature ofNumber Temperature of the Additive of the Sensitive (encapsulatedSensitive Chemical Electrons Compound sensitive Compounds StructureReleased (° C.) compound) (° C.) Copper (I) Salts Cu⁺ 1 >700 >700 SulfurSalts S₈ 6 100 246 Ascorbic Acid

2 190 241 Citric Acid

1 175 230

The polymeric matrix according to the present invention is preferablycomprised of non-polar polymers, preferably polyolefinic polymers, morepreferably polyethylenes and polypropylenes, since the active andintelligent additive according to the present invention evidencescompatibility with the polyolefin matrix due to its hybridfunctionality. The hybrid matrix further presents the advantage ofwithstanding the extrusion conditions (200° C.) required for thepreparation of the mixture.

The release of electrons and/or photons from the intelligent additivewhen dispersed in the polymeric matrix occurs when the polymer is in thepresence of compounds of the amino, amide, or oxygen-reducing types orvapors thereof, as well as in the presence of any substance that mightgenerate volatile or non-volatile oxygen-reducing compounds. Thosesubstances, on interacting with the additive, cause the latter torelease electrons and/or photons into the medium (polymer). Preferablywhen the medium is a polyolefin matrix, due to the difference inpolarity (charge) between the electron and the polyolefin, the freeelectrons will tend to preferably migrate to the surface of the article.

The identification of the analyte is achieved by means of the colorchange caused by the release of electrons, as will be better explainedin the examples below herein. Furthermore, the free electrons mayadditionally modify the electrical conductivity or resistance of thematerials.

Such active and intelligent additive, when used as an antimicrobialagent, has the advantage, in comparison with other additives alreadycommercially known as antimicrobial agents (silver salts, Triclosan,etc.), of not requiring direct contact of the additive with themicroorganisms, since the antimicrobial effect is provided by theelectrons that were released to the surface of the article, and theinteraction of the electrons with the outer membrane of themicroorganism or fungus (peptidoglycan, n-acetyl glucosamide, n-acetylmuranic acid) causes the rupture of the membrane and the subsequentdeath of the microorganism or fungus. In addition, the intelligentadditive according to the present invention is not toxic, and it ispossible to use the same in foodstuffs packages, and allows the activeand/or intelligent film to be directly manufactured without requiringextra steps to such end. Furthermore, the present invention also relatesto the products obtained from the incorporation of active andintelligent additives to polymeric matrices, that is, special polymericcompositions, as well as the respective articles, which exhibit specificproperties for different applications.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a Bode Graph obtained by EIS [Electrochemical ImpedanceSpectroscopy], commonly used to analyze the changes in electricalresistance of materials, wherein the electrochemical impedance module iscompared against the sine wave frequency, and shows the change ofelectrical resistance of the polymeric film comprising the active andintelligent additive after exposure to the ammonia vapors.

FIG. 2 illustrates a graph that reflects the microbiological growth ofPseudomonas against shelf storage time in samples of chicken packagedwith additive films using the active and intelligent additive.

EXAMPLES

The examples described herein relate to preferred embodiments of thepresent invention, and are thereby provided for purposes that are merelyillustrative rather than limitative, so they should not be construed toconstitute restrictions or to limit the scope of the present invention,whereby the latter should be interpreted in accordance with the scope ofthe claims attached herein.

The examples to follow are related to the obtainment of the active andintelligent additives, the activity thereof in identifying some analytesand the incorporation of such additives into polymer matrices.

Obtainment of the Active and Intelligent Additive

In general, in a preferred embodiment of the present invention, theactive and intelligent additives are obtained by way of the followingsteps:

a) Preparation of a solution of the sensitive compound by dissolving acertain amount of this compound in a certain amount of solvent thatconstitutes the reaction medium itself. The amount of the sensitivecompound vary from 0.005 grams to 1,000 grams dissolved within the rangeof from 1.0 mL to 100 L, at ambient temperature, whereby are obtainedwide ranges of concentration.

b) Addition of the compounds obtained from the sol-gel reaction to item(a). Initially the pH value is conditioned by means of the addition ofan acid or a base, as known in the art. Upon establishing the desired pHvalue, there are added the determined titanium or silicon alkoxides togenerate the encapsulation of the electron-releasing compound (sensitivecompound). The encapsulation by means of the addition of titanium orsilicon alkoxides occurs by means of the control of the type ofalkoxides, pH, temperature, time and the alkoxides/water ratio. With thedetermination of these variables there is controlled the relativepercentage of organic and inorganic groups, that is, the degree ofhybridism thereof.

c) Drying the suspension having been generated (if the active andintelligent additive was added in the form of powder).

The active and intelligent additive prepared in steps a, b and c, whendispersed in polymeric matrices, will evidence the releasing ofelectrons and/or photons upon interacting with amino, amide or oxygenreducing substances, either or not in the form of vapor. In addition itevidences a good dispersion ability and good compatibility as providedby the hybrid characteristic of the additive and by its thermal andmechanical stability.

The active and intelligent additive according to the present inventionmay be used as an antimicrobial agent, an indicator of the presence ofan analyte, an indicator of communication (may be detected with thepresence of a chip or another common electronic means), a generator ofenergy, an electrical conductor or electrical resistance reducer of aspecific material, or for any other application that might require thepresence of free electrons.

1—Preparation of the Active and Intelligent Additive in the Form ofPowder and Provision of Evidence of the Release of Electrons and ofColor Change

The active and intelligent additive was obtained in accordance with thefollowing methodology: 1.0 g of the sensitive compound (copper Ichloride) was dispersed in a mixture of 5 mL of deionized H₂O and 0.1 mLof concentrated HCl. Thereupon there were added thereto 4 mL of TEOS(tetraethyl orthosilicate) and 6 mL of OTMSi (octyl trimethoxysilane),or MTMSi (Methyl trimethoxysilane), or VTMSi (vinyl trimethoxysilane).The organosilanes reacted for 1 hour at ambient temperature and beingsubjected to mechanical stirring. Upon that time having elapsed, thesolid product was ground until the particle size thereof reached themicron range and was washed with water until the washing residue becamecolorless, and was subsequently dried in an oven at 80° C. There wasfinally obtained an active and intelligent additive in the form ofpowder and having a greenish hue (Cu⁺).

For purposes of evidencing the active and intelligent action thereof,the additive obtained in Example 1 above was subjected to a basic gas(NH₃) at ambient temperature. The solid obtained thereby acquired abluish color (Cu²⁺) on reacting with ammonia, thereby evidencing therelease of electrons by the copper oxidation reaction and theidentification of amino compounds by the change in color, at ambienttemperature.

The release of electrons took place by way of the following reaction:Cu⁺→Cu²⁺ +e ⁻

As previously set forth, the electron release may be used for thefunction of antimicrobial agent in an active package, and the colorchange may be used in an intelligent package for visual detection of ananalyte. For example, foodstuffs undergoing a putrefaction processusually release amino compounds such as ammonia, due to the action ofbacteria and fungi that transform the amino acids into gasses, and theelectrons release in this case points out the presence of the ammonia byway of the change of color of the copper and further attacks thebacteria present therein, as previously explained, evidencing thereby anintelligent action (identification of the analyte by color change) andan active (antimicrobial) action.

2—Incorporation of the Active and Intelligent Additive into ThePolymeric Matrix and Evidencing the Release of Electrons and the Changein Color

The incorporation of the active and intelligent additive into thepolymeric matrix was performed using standard extrusion procedures forpolymer processing, such as temperature profile, type of thread and typeof extruder normally used in an additivation process. Upon theincorporation of the active and intelligent additive into the polymer,there were fabricated films using a balloon-type film extruder, wherethe thickness of the films was between 10 and 100 μm.

The evidence of release of the electrons by the active and intelligentadditive after incorporation of the same into the polymeric matrix wasprovided by the change in Electric (Ohmic) Resistance of the films. Theelectrical resistance property is characteristic for each type ofmaterial, as are the fusion heat, the density, etc. To such end, thefilms were exposed to ammonia vapors and were compared with the filmsthat were not subjected to exposure to the ammonia vapors. Themeasurements of electrical resistance were made using theElectrochemical Impedance Spectroscopy (EIS) technique, which consistsin the excitation of an electrochemical cell by a sine wave signal andthe respective analysis of the current produced thereby. By means of thedue mathematical treatment of that response, one is able to obtain theImpedance and the Ohmic Resistance of the material that is beingsubjected to measurements.

The graph of FIG. 1 represents the module of electrochemical impedanceas a function of the frequency of the sine wave, wherein there may beobserved the curve (a) which represents the impedance of the film withthe additive incorporated therein, the curve (b) which represents theimpedance of that same film, however in contact with NH₃ gas, and thecurve (c) which corresponds to the metallic copper (for purposes ofcomparison with conductive metals). There may be also noted an ampledecrease of impedance of the film having the active and intelligentadditive incorporated therein, in the presence of vapors of ammonia(NH₃), when compared with the film with no presence of NH₃. Thepolymeric film without the addition of the active and intelligentadditive does not evidence any kind of change, since this is a propertyof the material and it is not affected by an external chemical action.

If compared with the curve (c) of the metal, we may note that,relatively to the presence of ammonia, the behavior of the filmincluding the additive approximates the behavior of a metal, in whatconcerns the presence of electrons on the surface.

In Table 2 one may observe the decrease in electrical resistance of thedescribed materials, once again confirming the release of electrons whenin contact with the vapors of an analyte (ammonia). The former evidencesthe functioning of the active and intelligent additive when dispersed ina polymeric matrix, functioning as a releaser of electrons, whichprovides thereto suitability for all the applications that have beenpreviously described herein. It may be noted that for the describedfilms, the electrical resistance decreases in the order of 10³ to 10⁴Ohms when in the presence of NH₃ gas. This is caused by the release ofelectrons from each of the different films having been fabricated.

When compared with the pure film devoid of additive, one may observethat the decrease of electrical resistance of the film with the activeand intelligent additive incorporated therein, in the presence ofammonia, is about 100 to 1000 times. The former shows that the activeand intelligent additive has the ability to change the electricalresistance characteristics of the materials, providing a wide range ofnew applications. The former could present distinct applications such asa switch, which in the presence of a certain analyte allows thecommunication of specific environment conditions, either by way of therelease of electrons or by changing color.

TABLE 2 Decrease of the electrical resistance of the films by therelease of electrons. Electrical Electrical resistance in the Filmresistance presence of NH₃ vapor Pure film without  6.7 × 10¹⁰ Ω 1.5 ×10⁹ Ω additive Film with additive 7.0 × 10⁹ Ω 1.1 × 10⁵ Ω based oncitric acid Film with additive 1.6 × 10⁹ Ω 3.0 × 10⁵ Ω based on sulfurFilm with additive 6.2 × 10⁹ Ω 2.2 × 10⁶ Ω based on copper (I)

This demonstrates the presence of free electrons in the polymeric filmwhen arising from the contact of the active and intelligent additivewith an analyte (ammonia vapor).

3—Evidence of the Antimicrobial Action of the Films Whereto was Addedthe Active and Intelligent Additive.

The methodology used to determine the antimicrobial effect was practicedby means of the total bacteriological count of microorganisms,specifically Pseudomonas, varying the shelf storage time of thefoodstuff.

Method: Pieces of chicken breast of approximately 50 grams each werepackaged with the films provided with the active and intelligentadditive. These films, containing the chicken breasts, were sealed inthe form of bags, thereby simulating the shelf storage conditions of thepackaged foodstuff. Subsequently the said bags containing the chickenbreasts were packaged in a secondary bag of polyolefin film (without theincorporation of the active and intelligent additives) using vacuum (thesame test may be conducted using a film co-extruded with anadditive-bearing layer and a layer with no additive). The innermostlayer, which contains the additive, is intended for the purpose ofperceiving the electrons released by the volatile compounds produced bythe degradation of the foodstuff and to promote the migration thereof tothe surface of the film which is in direct contact with the foodstuff(innermost surface) rather than to the outer part, in which, in thisspecific case, it would not evidence any advantage, being devoid ofantimicrobial efficiency (which would occur by means of the loss of theelectrons to the external surface). Subsequently to the packaging, therewere conducted the analyses of counting of Pseudomonas once every threedays to determine the microbiological growth as a function of time andto observe the antimicrobial action of the polymeric films additivatedwith the active and intelligent additives.

In the graph of FIG. 2, the samples used for the study were thefollowing:

LHB: Polyolefin film (without incorporating the active and intelligentadditive).

CuV-10/E3: LHB with the incorporation of the Copper-based active andintelligent additive and a hybrid ratio TEOS/VTMSi (vinylic)

CuC8-10/E5: LHB with the incorporation of the Copper-based active andintelligent additive and a hybrid ratio TEOS/OTMSi (octyl)

CuC1-20/E4: LHB with the incorporation of the Copper-based active andintelligent additive and a hybrid ratio TEOS/MTMSi (methyl)

ACV-10/E2: LHB with the incorporation of the Citric Acid-based activeand intelligent additive and a hybrid ratio TEOS/VTMSi (vinylic)

There may be noted an exponential growth of the Pseudomonas that wasequal for all samples up until the seventh day, when there was reached aconcentration of 1×10⁶ UFC. After 7 days, the samples of CuC8-10/E5,CuCl-20/E4 and ACV-10/E2 evidenced a reduction in the growth of thePseudomonas. The sample CuC8-10/E5 evidenced the best behavior inreducing the growth of Pseudomonas, and specifically with this samplethere was once again achieved the value of 1×10⁶ UFC on the 11^(th) day.These results clearly show the microbiological growth inhibiting effectin the samples of film comprising the active and intelligent additives.Specifically, the sample that evidenced a greater level of efficiency inreducing the microbiological growth was the sample identified asCuC8-10/E5. This constitutes extremely strong proof of the effect asinhibitor of microbiological growth of Pseudomonas in samples of chickenbreast, when the latter were packaged using the films that wereadditivated using the active and intelligent additives according to thepresent invention. Thus, there may be established an increase of 4 daysin the useful time of the said foodstuff and there has been demonstratedthe use of the packages made with these films provided with theadditives according to the present invention as constituting active andintelligent packages.

The reduction of growth of Pseudomonas was due to the release of theelectrons contained in the active and intelligent additives, which whenplaced in contact with the gasses produced by the decomposition of thechicken, evidence the release of electrons, whereby the cited electronsinteract with the Pseudomonas, inhibiting the growth of the latter.

All documents cited in the present document are incorporated hereto forpurposes of reference, as regards the relevant part thereof. Thecitation of any document should not be construed as an admission of thefact that the same might represent prior art with relation to thepresent invention. Although there were illustrated in the examples anddrawings attached hereto, and described in the instant specification,some preferred embodiments of the invention, it should be obvious to atechnician skilled in the art that the invention is in no way limited tothe realizations thereof as described herein, and there should be ratherconstrued that other alterations, modifications and substitutions may bemade without deviating from the characteristic nature and scope of theinvention, which is defined in the claims attached hereto.

The invention claimed is:
 1. A polyolefin package material comprising anactive and intelligent additive incorporated within an innermost layerof polyolefin package materials and formed of a sensitive compoundencapsulated in an inorganic matrix with hybrid characteristics, saidinorganic matrix with hybrid characteristics formed by a siliconalkoxide or a titanium alkoxide, wherein said sensitive compoundreleases electrons and/or photons as an antimicrobial agent in thepresence of a reactive chemical compound by means of a reaction ofcorrosion of the encapsulated sensitive compound, said reactive chemicalcompound comprising any compound present in a medium that activates saidsensitive compound, wherein said sensitive compound is selected from thegroup consisting of copper (I), sulfur, ascorbic acid and citric acid,and wherein said silicon alkoxide is selected from the group consistingof tetraethyl orthosilicate, ethyl triethoxysilane, methyltriethoxysilane, phenyl triethoxysilane, methyl trimethoxysilane,n-octyl ethoxysilane, n-butyl ethoxysilane and vinyl trimethoxysilane,and said titanium alkoxide is selected from the group consisting oftetraethoxy titanium, ethyltriethoxy titanium, methyltriethoxy titanium,phenyltriethoxy titanium, n-octylethoxy titanium and n-butylethoxytitanium, and wherein the package materials with the additive haveantimicrobial activity.
 2. The polyolefin package material as recited inclaim 1, wherein said reactive chemical compound is selected from thegroup consisting of amino compounds, amide compounds, oxygen-reducingcompounds and/or vapors thereof.
 3. The polyolefin package material asrecited in claim 1, wherein said polyolefin is a polyethylene.
 4. Thepolyolefin package material as recited in claim 1, wherein saidpolyolefin is a polypropylene.
 5. The polyolefin package material asrecited in claim 1, wherein said additive acts as an indicator of gaspresence caused by decomposition of foodstuffs.